American and Chinese defense officials on Monday expressed a willingness to work together to address the growing threat of cyber attacks.

There is growing concern among U.S. officials, lawmakers and cyber security experts that America's defense, business and economic interests are increasingly threatened by foreign cyber attacks. And often, China is cited as the source of these intrusions.

But that is something visiting Chinese Defense Minister Liang Guanglie denied during a press conference at the Pentagon.

Liang, a general in the People's Liberation Army, said that there is no evidence directly linking cyber attacks in the United States to China. He said that in his talks with U.S. Secretary of Defense Leon Panetta, the secretary agreed that all of the attacks could not be attributed to China.

Liang said that during their talks Monday, he and Panetta discussed ways to strengthen cyber security, but added that they would leave the details of that effort for experts to work out.

President Barack Obama has cited cyber security as one of the most serious economic and national security challenges facing the United States. Defense Secretary Leon Panetta says Sino-American cooperation is crucial.

“Because the United States and China have developed technological capabilities in this arena, it’s extremely important that we work together to develop ways to avoid any miscalculation or misperception that could lead to crisis in this area," said Panetta.

During high-level talks last week in Beijing, cyber security was among the major issues discussed by civilian and military leaders. Secretary of State Hillary Clinton said that during the annual Strategic and Economic Dialogue, the United States expressed its growing concern about the threat cyber intrusions pose to economic and national security across the world. She stressed the need for the world’s two biggest cyber actors - the United States and China - to have a sustained, meaningful dialogue on cyberspace and to develop a shared understanding of acceptable norms of behavior.

But the push for cooperation and the fact that not all cyber attacks originate in China do not mean that Washington is unconcerned about the role Beijing plays in such intrusions. Last year, a report issued by U.S. intelligence agencies listed Chinese actors in cyberspace as the most active and persistent perpetrators of economic espionage. Russia’s intelligence services were also cited for using cyberspace to collect economic information and acquire U.S. technology.

The report said that although private U.S. firms and cyber security specialists have reported a massive number of intrusions that originated in China, it is difficult to determine who is ultimately responsible.

Beijing says it is the biggest victim of cyber attacks, noting that last year some 47,000 foreign Internet addresses were involved in attacks on nearly nine million computers in China.

In addition to cyber threats, the two defense officials discussed a range of other issues, including North Korea’s nuclear program, U.S. arms sales to Taiwan and territorial disputes in the South China Sea.